Spermonde Archipelago Research Articles

Impact of human interventions on mangrove ecosystem in spatial perspective

Climate change components that affect mangroves include changes in sea level, high water events, storms, precipitation, temperature, and oceanic circulation. Cumulative impacts of these factors have a distinct synergy with respect to an accelerated rate of mangrove degradation. development of coastal agricultural land and shrimp farming ponds in intertidal areas are considered as the major factors behind mangrove delineation. There is no agreement for the extensive of mangrove forest in Indonesia, but invarious forums it is usually used the number of 4.25 million ha for that. At approximately 9 years ago, the extensive vast of mangrove forest in Indonesia was about 4.13 million ha but now it is only 2.49 million ha (60%). The methodology of this study consisted of two main steps: (1) image analysis, and (2) post classification. The aim of this study is to analysis the human intervention base on spatial dynamic of mangrove. The study site was selected Sagara island in Spermonde Archipelago. The results of analyze shows that decreasing of mangrove is caused human intervention.

The role of patron-client relations on the fishing behaviour of artisanal fishermen in the Spermonde Archipelago (Indonesia)

Patron-client systems are ubiquitous in small-scale fisheries and are thought to have an important role on the way marine resources are exploited. With the aim of identifying key differences between fishermen with a patron and independent fishermen, questionnaires were used to obtain individual socio-demographic characteristics and perceptions of fishing behaviour of fishermen in Spermonde (Indonesia). Catch assessments of landings were carried out and differences between dependent and independent fishermen evaluated. Fishermen with patrons had more valuable catch with a higher portion of live fish while independent fishermen were more engaged in subsistence fishing. Fishermen with patrons had higher turnovers than independent fishermen, but this result was contested after accounting for additional costs resulting from their indebtedness. Comparison between perceived and empirically measured data showed that fishermen with patrons underestimated their expected daily catch. The results suggest that belonging to the patron-client system affects fishing behaviour by making fishermen use less diversified gears and increase their focus on commercial fishing. The consequence of this is an apparent reduced amount of seafood provision for the household and possibly greater ecological impact due to the use of cyanide, a destructive fishing method. While the patron-client system has gained attention as a potential institution to promote sustainable exploitation practices, the data analysed here suggest that the patron-client relationship indirectly causes a worse environmental impact by encouraging higher exploitation rates. The implications are that bringing the patron-client system on board sustainable fishing policies may require context-dependent considerations of cultural obstacles and social complexities.

RATIO OF NUTRIENT AND DIATOM-DINOFLAGELLATE COMMUNITY IN SPERMONDE WATERS, SOUTH SULAWESI

<p><em>Runoff of nutrients (N, P, Si) from the mainland would disrupt the balance of nutrients in the waters resulted in changing microalgae communities composition, especially between diatom and dino-flagellate (Dia/Dino). This study was aimed to analyze the relationship of nutrient ratios (N/P, N/Si, Si/P) in the waters, to the density ratio of the Dia/Dino in the coastal and marine waters of Spermonde archipelago, South Sulawesi, Indonesia, which experience nutrient enrichment. Nutrients and phyto-plankton samples were collected from the coastal waters of Tallo, Maros, Pangkep, and seawaters of Spermonde in three seasons (transition, wet, and dry). The results showed the average value (± stan-dard deviation) of Dia/Dino ratio in the coastal and sea waters is 1422±1742 and 1174±1290 in the transition season; 238±205 and 1039±2264 in the dry season; and 153±270 and 72±71in the rainy season. Meanwhile, in the marine waters the ratio of Dia/Dino ranges between 1 and 9839. The ratio of Dia/Dino was not different significantly (p>0,05) by spatial and temporal, but Dia/Dino ratio was different significantly (p<0,05) on the ratio of nutrients in coastal waters, where the value of N/Si ratio tends to ignite monospesies enrichment diatom (Chaetoceros) with a variant of 70,4%.</em></p><p><em> </em><strong><em>Keywords</em></strong><em>: nutrient ratios, diatom, dinoflagellate, coastal, Spermonde</em></p>

RATIO OF NUTRIENT AND DIATOM-DINOFLAGELLATE COMMUNITY IN SPERMONDE WATERS, SOUTH SULAWESI

Runoff of nutrients (N, P, Si) from the mainland would disrupt the balance of nutrients in the waters resulted in changing microalgae communities composition, especially between diatom and dino-flagellate (Dia/Dino). This study was aimed to analyze the relationship of nutrient ratios (N/P, N/Si, Si/P) in the waters, to the density ratio of the Dia/Dino in the coastal and marine waters of Spermonde archipelago, South Sulawesi, Indonesia, which experience nutrient enrichment. Nutrients and phyto-plankton samples were collected from the coastal waters of Tallo, Maros, Pangkep, and seawaters of Spermonde in three seasons (transition, wet, and dry). The results showed the average value (± stan-dard deviation) of Dia/Dino ratio in the coastal and sea waters is 1422±1742 and 1174±1290 in the transition season; 238±205 and 1039±2264 in the dry season; and 153±270 and 72±71in the rainy season. Meanwhile, in the marine waters the ratio of Dia/Dino ranges between 1 and 9839. The ratio of Dia/Dino was not different significantly (p>0,05) by spatial and temporal, but Dia/Dino ratio was different significantly (p<0,05) on the ratio of nutrients in coastal waters, where the value of N/Si ratio tends to ignite monospesies enrichment diatom (Chaetoceros) with a variant of 70,4%. Keywords: nutrient ratios, diatom, dinoflagellate, coastal, Spermonde

The Use of C/N Ratio in Assessing the Influence of Land-Based Material in Coastal Water of South Sulawesi and Spermonde Archipelago, Indonesia

Measurement of C-N magnitude and C/N ratio from particulate matter is used to explain the source of terrestrial and sea particulates. Therefore, this study aimed at using C/N ratio in assessing land-based material in the west coast of Spermonde area, Indonesia on suspended matter. Samples of SPM were collected in two seasons (transition and dry seasons), in coastal waters of Tallo, Maros, and Pangkep estuaries. The results of research showed that Ctot was more abundant than was Ntot in particulates from river rather than from sea region, reflecting most of the terrestrial organic matter stored before meeting with sea. C/N ratio on the west coast of South Sulawesi was in the range of 7-19.7, showing that organic matter in Tallo estuary in transition season was dominantly autochthonous, while in dry season it was found to be dominantly terrigenous organic matter that gave an indication that land factor was significant in waste supply. The same thing was found in Maros estuary and Pangkep estuary in transition season and dry season; at all points of observation there were findings of particulates coming from terrigenous organic matter. Percentage of nutrient absorbed in particulate was low and could become a eutrophication stressor, where SPM found only ranged from 9.60 to 55.1 mgL-1 with maximum average in dry season and minimum in transition season. On the contrary, POM was maximum in transition season and minimum in dry season with dominant particulate organic matter source from the sea itself.

Experimental analysis of the effects of consumer exclusion on recruitment and succession of a coral reef system along a water quality gradient in the Spermonde Archipelago, Indonesia

The composition of coral reef benthic communities is strongly affected by variation in water quality and consumer abundance and composition. This is particularly evident in highly populated coastal regions where humans depend on coral reef resources and where terrestrial run-off can change the chemical composition of the water. We tested the effects of grazing pressure and ambient water conditions along an established eutrophication gradient on the recruitment and successional development of benthic communities of the Spermonde Archipelago, Indonesia, through caging experiments with settlement tiles. Within 1 month, benthic community composition of the closest reef to land, near the city of Makassar, was significantly different from other sites further offshore, driven primarily by differences in recruitment of invertebrates or turf algae. In contrast to other caging experiments, consumer exclusion had no effect after 3 months, suggesting that larger, mobile consumers had little effect on the benthic communities of these reefs at all sites. Despite conditions that usually favour macroalgal development, this group was rarely observed on recruitment tiles even after 4 months of consumer exclusion. Furthermore, tiles from both the caged and open treatments retained high proportions of open space indicating the possible role of small-sized or non-fish consumers that were not excluded from the experiment. These results indicate that, unlike many other studies, benthic consumers in the Spermonde Archipelago had little effect on the recruitment and early succession of the reef habitat and that unexamined biota such as mesograzers may be significant in degraded systems.

Habitat and water quality variables as predictors of community composition in an Indonesian coral reef: a multi-taxon study in the Spermonde Archipelago

Assemblages of corals, sponges, foraminifera, sediment bacteria and sediment archaea were assessed at two depths in the Spermonde Archipelago. Our goal was to assess to what extent variation in composition could be explained by habitat and water quality variables. The habitat variables consisted of depth, substrate type and scleractinian coral cover while water quality variables were derived from ocean color satellite imagery, including the colored dissolved organic matter index (CDOM), chlorophyll-a (Chlor-a) and remote sensing reflectance at 645nm (Rrs_645). Together, habitat and water quality variables explained from 31% (sediment bacteria) to 80% (forams) of the variation in composition. The variation in composition of corals, sponges, forams and sediment archaea was primarily related to habitat variables, while the variation in composition of sediment bacteria was primarily related to water quality variables. Habitat and water quality variables explained similar amounts of variation in the composition of corals and sediment bacteria. CDOM (sponges, sediment bacteria and sediment archaea), Chlor-a (corals and forams) and Rrs_645 (sponges and forams) proved significant predictors of variation in composition for the studied taxa. In addition to water quality variables, all taxa responded to a range of habitat variables including depth and the percentage cover of various benthic life forms including coral cover variables, rubble and sand. Sand cover was the most important habitat variable for corals, sponges, sediment bacteria and sediment archaea. Coral life forms including the cover of branching and tabular corals were important habitat variables for sponges and forams. These results show marked differences in how various taxa respond to variation in habitat and water quality in the Spermonde Archipelago. Moreover, our results indicate that variables estimated from ocean color satellite imagery proved to be better predictors of variation in marine community composition than commonly-used proxies such as the distance offshore or distance to the nearest river.

Of exploited reefs and fishers – A holistic view on participatory coastal and marine management in an Indonesian archipelago

This paper arises from a four-year Indonesian-German research cooperation on the governance and management of Indonesian coastal and marine ecosystems. Project objectives were to investigate coastal and marine social-ecological dynamics and feedbacks and to analyse socio-political and institutional structures and processes in order to support adaptive coastal governance. Participating researchers worked in the Spermonde Archipelago, off South Sulawesi, Indonesia, between 2007 and 2010. Methods included ship-based research excursions, several classical surveys, anthropological participant observation, and participatory research methods applied by an interdisciplinary social-natural science team. This paper summarises our findings and draws policy conclusions. First, we discuss Marine Protected Areas and participation focussing on local “rules-in-use”. In addition, reef exploitation and local livelihoods, in particular fisheries and mariculture, and the existing social networks and hierarchies in fisheries are explored to understand social vulnerability, resilience and marine resource governance in the context of the Spermonde Archipelago. An outline of major policy recommendations concludes this article.

Composition and Predictive Functional Analysis of Bacterial Communities in Seawater, Sediment and Sponges in the Spermonde Archipelago, Indonesia.

In this study, we used a 16S rRNA gene barcoded pyrosequencing approach to sample bacterial communities from six biotopes, namely, seawater, sediment and four sponge species (Stylissa carteri, Stylissa massa, Xestospongia testudinaria and Hyrtios erectus) inhabiting coral reefs of the Spermonde Archipelago, South Sulawesi, Indonesia. Samples were collected along a pronounced onshore to offshore environmental gradient. Our goals were to (1) compare higher taxon abundance among biotopes, (2) test to what extent variation in bacterial composition can be explained by the biotope versus environment, (3) identify dominant (>300 sequences) bacterial operational taxonomic units (OTUs) and their closest known relatives and (4) assign putative functions to the sponge bacterial communities using a recently developed predictive metagenomic approach. We observed marked differences in bacterial composition and the relative abundance of the most abundant phyla, classes and orders among sponge species, seawater and sediment. Although all biotopes housed compositionally distinct bacterial communities, there were three prominent clusters. These included (1) both Stylissa species and seawater, (2) X. testudinaria and H. erectus and (3) sediment. Bacterial communities sampled from the same biotope, but different environments (based on proximity to the coast) were much more similar than bacterial communities from different biotopes in the same environment. The biotope thus appears to be a much more important structuring force than the surrounding environment. There were concomitant differences in the predicted counts of KEGG orthologs (KOs) suggesting that bacterial communities housed in different sponge species, sediment and seawater perform distinct functions. In particular, the bacterial communities of both Stylissa species were predicted to be enriched for KOs related to chemotaxis, nitrification and denitrification whereas bacterial communities in X. testudinaria and H. erectus were predicted to be enriched for KOs related to the toxin-antitoxin (TA) system, nutrient starvation and heavy metal export.

A recent outbreak of crown-of-thorns starfish (Acanthaster planci) in the Spermonde Archipelago, Indonesia

A recent review of crown-of-thorns starfish (Acanthaster planci; COTS) in Indonesia has suggested that their impacts have gone under-reported. In 2012–2013, we surveyed COTS at permanent transects within 12 sites of the Spermonde Archipelago, Indonesia, a coastal region close to two rivers and the heavily urbanised city of Makassar. Evidence of COTS was apparent at 8 of 12 sites surveyed with highest densities (37 starfish per 250 m−2 at Barrang Lompo) comparable to those reported in the Indonesian historical literature. At Barrang Lompo and Bonetambung, the COTS outbreak resulted in the loss of half the live coral. Terrestrial effluents have reduced water quality in the Spermonde Archipelago, which further supports recent work linking water quality and COTS outbreaks, thus providing a warning of future outbreaks to Indonesian coastal managers given the country’s increased urbanisation.

Multisensor and multitemporal data from Landsat images to detect damage to coral reefs, small islands in the Spermonde archipelago, Indonesia

Coral reefs are important because of their high biodiversity and their key role in the tropical marine biosphere. Furthermore, coral reefs are very valuable as a socioeconomic resource as they make important contributions to the gross domestic product of many countries. Thus, it is very important to monitor dynamic spatial distributions of coral reefs and related habitats dominated by coral rubble, dead coral, and bleached corals. Despite these natural and socio-economic advantages, many factors are threatening coral reefs. The study site was selected in Spermonde archipelago, South Sulawesi, Indonesia because this area is included in the Coral Triangle, recognized as the epicenter of coral diversity and a priority for conservation. Images of Landsat MSS, Landsat TM, Landsat ETM, Landsat ETM+, and Landsat 8 data were used to examine changes in the coral reefs of Suranti Island in the Spermonde Archipelago during forty one years from 1972 to 2013. The image processing includes gap fills, atmospheric corrections, geometric corrections, image composites, water column corrections, unsupervised classifications, and reclassifications. Fill Gap processing was done on Landsat ETM+ SLC-off. Subsequently, a multi-component change detection procedure was applied to define changes. Shallow water bottom types classification was divided into live coral, rubble and sand habitats, dead coral with algae, rubble, and sand. Preliminary results showed significant changes during the period 1972–2013 as well as changes in coral reefs, likely explained partly by destructive fishing practices.

Introduction of geospatial perspective to the ecology of fish-habitat relationships in Indonesian coral reefs: A remote sensing approach

Coral reef ecosystems worldwide are now being harmed by various stresses accompanying the degradation of fish habitats and thus knowledge of fish-habitat relationships is urgently required. Because conventional research methods were not practical for this purpose due to the lack of a geospatial perspective, we attempted to develop a research method integrating visual fish observation with a seabed habitat map and to expand knowledge to a two-dimensional scale. WorldView-2 satellite imagery of Spermonde Archipelago, Indonesia obtained in September 2012 was analyzed and classified into four typical substrates: live coral, dead coral, seagrass and sand. Overall classification accuracy of this map was 81.3% and considered precise enough for subsequent analyses. Three sub-areas (CC: continuous coral reef, BC: boundary of coral reef and FC: few live coral zone) around reef slopes were extracted from the map. Visual transect surveys for several fish species were conducted within each sub-area in June 2013. As a result, Mean density (Ind. / 300 m2) of Chaetodon octofasciatus, known as an obligate feeder of corals, was significantly higher at BC than at the others (p < 0.05), implying that this species’ density is strongly influenced by spatial configuration of its habitat, like the “edge effect.” This indicates that future conservation procedures for coral reef fishes should consider not only coral cover but also its spatial configuration. The present study also indicates that the introduction of a geospatial perspective derived from remote sensing has great potential to progress conventional ecological studies on coral reef fishes.

What lies beneath: Why knowledge of belowground biomass dynamics is crucial to effective seagrass management

Conservation of seagrasses meadows is important, because these habitats are ecologically important and under threat. Monitoring and modelling are essential tools for assessing seagrass condition and potential threats, however there are many seagrass indicators to choose from, and differentiating between natural variability and declining conditions poses a serious challenge. Tropical seagrass meadows in the Indo-Pacific, in contrast to most temperate meadows, are characterized by a multi-species composition and a year-round growth. Differences in characteristics between species growing within one meadow could induce uncertainty in the assessment of the dynamics of these meadows if variation in productivity and related biomass turnover timescales are not taken into consideration. We present data on biomass distribution, production and turnover timescales of above- and belowground tissues for three key tropical seagrass species (Thalassia hemprichii, Cymodocea rotundata and Halodule uninervis) in two mixed-species meadows in the Spermonde Archipelago, Indonesia. Seagrass leaf turnover time scales were comparable for the three studied seagrass species and varied between 25 and 30 days. Variation in leaf and rhizome turnover timescales were small (or insignificant) between the two meadows. In contrast, rhizome turnover time scales were around ten times longer than leaf turnover timescales, and large differences in rhizome turnover time scales (200–500 days) were observed between the species. The late-successional species T. hemprichii had much slower rhizome turnover compared to the two early successional species. Furthermore, since rhizome biomass has a much longer turnover time compared to leaf biomass, changes in rhizome biomass reflect effects on seagrass meadows on a much longer timescale compared to changes in leaf biomass for these tropical meadows. We conclude that belowground biomass dynamics are an important proxy to assess long-term effects of environmental stressors on seagrass ecosystems and should be included in tropical seagrass management programmes.

Fish herbivory as key ecological function in a heavily degraded coral reef system

AbstractLocalized impacts, such as eutrophication and overfishing, have been identified as major threats to reefs worldwide, resulting in changes in coral reef community composition, from coral‐dominance to algal‐dominance. Herbivory by fishes is frequently cited as a key process structuring benthic community response to stressors. Here, we experimentally tested the capacity of herbivorous fishes to remove macroalgae along an onshore–offshore spatial gradient in the Spermonde Archipelago, Indonesia; a coral reef system exposed to long‐term anthropogenic disturbances. Bioassays of Sargassum and Padina spp. were collected from the reef flat and transplanted onto the reef slope at five islands varying in distance (1–55 km) from the coastline and city of Makassar, South Sulawesi. Supplementary underwater video deployment and fish surveys were used to identify species‐specific differences in herbivore communities and rates of algal removal. Over a 24 h period, Padina was almost completely removed from the two outermost islands, but removal declined toward shore. With the exception of the site closest to Makassar, more than 50% of all transplanted macroalgae were removed. Species diversity of algal‐consuming fishes and total bites increased toward off‐shore, with only one species, Siganus virgatus (Siganidae), feeding at all sites. These changes in herbivore communities underline the capacity for functional resilience under varying levels of reef degradation. Our results exemplify the complexities of ecological functioning along environmental gradients.

Abundance and genetic variation of the coral-killing cyanobacteriospongeTerpios hoshinotain the Spermonde Archipelago, SW Sulawesi, Indonesia

The cyanobacteriospongeTerpios hoshinotais expanding its range across the Indo-Pacific. This species can have massive outbreaks on coral reefs, actively kill corals it overgrows and affect the entire benthic community. Although it has received much attention on the post-outbreak follow-up, little is known about its ecology, habitat preferences, and the possible environmental triggers that cause its outbreaks. We present a baseline study in the Spermonde Archipelago, Indonesia, whereT. hoshinotawas first observed in 2012. We surveyed 27 reefs and recorded patches between 14 and 217 cm2, at four reef sites (~15% cover). The sponge was found on both mid-shelf and outer shelf reefs but not close to the coast and the city of Makassar. Differences in benthic community structure, as well as spatial variables relating to the on-to-offshore gradient in the Spermonde archipelago, neither constrained nor promoted its expansion. Patches of the sponge were mostly overgrowing branching corals, belonging to Acroporidae species. Genetic variation withinT. hoshinotawas studied by sequencing partitions of the mitochondrial CO1 and nuclear ribosomal 28S gene. Two haplotypes were found within the Spermonde archipelago, which differed from the CO1 sequence in GenBank. The present study provides an indication of habitat preferences ofT. hoshinotain non-outbreak conditions, although it is still unclear which environmental conditions may lead to the onset of its outbreaks.

Microstructural analyses of sedimentary Halimeda segments from the Spermonde Archipelago (SW Sulawesi, Indonesia): a new indicator for sediment transport in tropical reef islands?

Understanding the origin of sediments and the direction of sediment transport is a prerequisite for accurate reconstruction of reef island evolution. In tropical settings, island development depends on the accumulation of sediments on the reef flat, which are produced by calcifying organisms such as corals, foraminifera, and green macro-algae of the genus Halimeda. In certain areas of tropical regions, calcareous segments from these algae might account for more than 50 wt% of the coarser sediment fraction. Halimeda-rich sediments typically contain complete segments that become widely distributed to a range of sedimentary settings. However, the exact sedimentary pathway is either mostly unknown or was neglected. Here we show that the alteration of Halimeda segments from the Spermonde Archipelago (SW Sulawesi, Indonesia) is related to processes during transport and deposition. Using field observations and scanning electron microscopy we observed that Halimeda segments, sampled from the reef flat to the shore on four uninhabited islands, without exception belong to the grain-size class of pebble gravel (1.6 > 0.4 cm; medium-to-fine pebbles) and reveal characteristic patterns of external and internal microstructural alteration with respect to sampling area. Furthermore, Halimeda species, from which most of these segments originate, preferably inhabit hard substrates in the reef, on the reef crest, and the outer reef flat. Thus, the observed distinct microstructural alteration of the segments allows drawing conclusions on sediment transport and deposition. Particularly, rapid secondary cementation may preserve the segments as a sedimentary component for the development and maintenance of reef islands and coastlines in tropical shallow seas.

Spectral Clustering of Coral Reefs on the Small Islands, Spermonde Archipelago, Indonesia

Authors' contributions This work was carried out in collaboration between all authors. Author NN design the study, wrote the protocol and first draft processed of the manuscript all the data, interpreted the results, and wrote the manuscript. Authors TK and HY managed the analysis of the study and gave a number of suggestions that significantly improved the paper. Authors CR and GA performed the statistical analysis and identified a coral species. Author MAAS managed the literature search. All authors read and approved the final manuscript. Article Information ABSTRACT Ecologically, coral reef has a function to protect the others component of marine and coastal ecosystem from pressure of wave and storm. If compared with the other ecosystems, coral reef that are most easily destroyed. Spermonde archipelago consist of more than one hundred small islands, which have the higher potential ecosystem especially of coral reef distribution. It is very influencing and provide higher contributes to the preservation of society, where most livelihoods depend on its shallow water and has high growing human activity. Remote Sensing technologies is an alternative to support the availability of spatial information resources, such as coral reefs in the large area. Original Research Article

Politics of technology in the informal governance of destructive fishing in Spermonde, Indonesia

Technology has politics and plays a role in societal governance. This article explores the fishing community of Karanrang island (Spermonde Archipelago, Indonesia) to consider how fishing technologies reinforce existing power structures in the local informal governance system. Informal governance actors deploy the politics of technology in order to manage a socially problematic and environmentally destructive fishing economy. In the punggawa-sawi system of patron-client relationships, fishers are economically dependent on patrons, who supply them with fishing technologies like boats, bombs, and cyanide. The patrons themselves are embedded in a complex governance network, encompassing corrupt police and officials, importers, and live food fish traders. The politics of technology contribute to maintaining the local informal governance system of patron-client relationships. This paper draws upon theories from science and technology studies and network governance to argue that although patron-client relationships are problematic in themselves, the politics of technology further maintain power imbalances.

The putative functional ecology and distribution of archaeal communities in sponges, sediment and seawater in a coral reef environment.

Archaea play crucial roles in a number of key ecological processes including nitrification and methanogenesis. Although several studies have been conducted on these organisms, the roles and dynamics of coral reef archaeal communities are still poorly understood, particularly in host and nonhost biotopes and in high (HMA) and low microbial abundance (LMA) sponges. Here, archaeal communities detected in six distinct biotopes, namely, sediment, seawater and four different sponge species Stylissa carteri, Stylissa massa, Xestospongia testudinaria and Hyrtios erectus from the Spermonde Archipelago, SW Sulawesi, Indonesia were investigated using 454-pyrosequencing of 16S rRNA genes (OTU cut-off 97%). Archaeal communities from sediment and sponges were dominated by Crenarchaeota, while the seawater community was dominated by Euryarchaeota. The biotope explained almost 75% of the variation in archaeal composition, with clear separation between microbial assemblages from sediment, X.testudinaria and H.erectus (HMA). In contrast, samples from seawater and both Stylissa species (LMA) showed considerable overlap in the ordination and, furthermore, shared most abundant OTUs with the exception of a single dominant OTU specifically enriched in both Stylissa species. Predicted functional gene content in archaeal assemblages also revealed significant differences among biotopes. Different ammonia assimilation strategies were exhibited by the archaeal communities: X.testudinaria, H.erectus and sediment archaeal communities were enriched for glutamate dehydrogenase with mixed specificity (NAD(P)(+) ) pathways, while archaeal planktonic communities were enriched for specific glutamate dehydrogenase (NADP(+) ) and glutamate synthase pathways. Archaeal communities in Stylissa had intermediate levels of enrichment. Our results indicate that archaeal communities in different biotopes have distinct ecophysiological roles.

The Profile of Secondary Metabolites of Sponge &amp;lt;i&amp;gt;Clathria reinwardtii&amp;lt;/i&amp;gt; Extract as a Result of Fe Accumulation in Spermonde Archipelago

Study on the effect of Fe metal concentrations in Spermonde Archipelago on secondary metabolites production from sponge was conducted. The percent of peak area and m/z from GC-MS at tR = 13.555 were affected by accumulated Fe in Chlathria reinwardtii, where at high Fe concentration a lower percent peak area was produced compared to Clathria rein-wardtii extract at low Fe concentration. Chromatogram CR-LL-DCM produced 2 peaks at tR = 21.401 and 25.174 which were not observed in CR-BC-DCM chromatogram. This indicated that Clathria reinwardtii in Lae-Lae island produced metabolite secondary compounds that were not produced by Clahtria reinwardtii in Barrang Caddi island. FT-IR analysis indicated that Clathria reinwardtii accumulating Fe with highest and lowest concentration produced strong peaks at wavenumber of about 3400 cm-1 for O-H and N-H stretches. O-H pliable and C-O stretch peaks at wavenumber of about 1200 cm-1 had changes from medium intensity at low Fe concentration (CR-BC-DCM) to weak at high Fe concentration (CR-LL-DCM).